CLEANING TELESCOPES &amp BINOCULARS

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CLEANING OPTICS -
MIRRORS
LENSES

PROTECTION BEATS CLEANING

TELESCOPE MIRRORS

The protection of the telescopes optics is far better than cleaning them. Cleaning optics
whether binoculars, refractors or reflectors can reduce
the light gathering power by scratching
or removing the enhanced coatings placed on them to improve their performance. A mirror
or lens will eventually
get dirty and below I have outlined how to clean them.

The best way to protect your mirrors or lenses is to use a good fitting dust cap/s. Dust caps
should be used on the eyepieces as they have enhanced coatings
on the lenses as well. If
you own a open tubed reflector like a Newtonian, it's best to put a dust cover over the end
of the tube where the main mirror is as well.
This main mirror cover can double as a cover
to block stray light from getting in around where the mirror is attached to the tube as most
reflectors have gaps
where the mirror is bolted in to allow air flow.

Keeping a telescope inside when not in use will preserve the reflective coatings for longer
and prevent any rusting. Aluminium coatings last about
8-10 years when they are kept
dry and clean. Any moisture on the telescope or its caps should be wiped dry before fitting
and putting away. Don't wipe the
mirrors or lenses dry if they have dew on them, but let
them dry naturally. Any water marks which may appear on mirrors through condensation
and dust can be
removed by firstly removing the mirror and pouring distilled water over
them. The distilled water will not leave any water marks.

CLEANING OPTICAL SURFACES

BINOCULARS AND REFRACTING TELESCOPES

When a mirror or a lens does get dirty it can reduce the reflectivity or light gathering power.

Refractor and binocular lenses are more forgiving than mirrored surfaces. However
it is quite easy to remove or scratch the coloured enhanced
coatings on binoculars and
refractors just by wiping with a soft cloth too hard. A quick check of the optics manual
will give suggestions to removing any unusual
marks or dirt without removing the enhanced
coatings. Otherwise a rub with a soft cloth is the only cure, but try using a soft brush first
(camel hair) or a "Lens
Pen". A Lens Pen has a soft brush at one end and at the other end
a special device for getting into corners and removing dirt or sand. Lens Pens are around
$15.00.